Delta herpesvirus (DHV) infection in Erythrocebus patas monkeys - A model for human herpes zoster complications: Experimental studies have indicated that patas monkeys become persistently infected with DHV. We are investigating how to activate this persistent infection in the monkey model. We have been unable to activate the persistent infection using immunosuppressive drugs to suppress the monkey's immune system. "Whole body irradiation" may be sufficient to allow reactivation of the DHV. A group of young cynomolgus Macaca fasiculorus monkeys were monitored for 30 months following intracerebral inoculation of "Biken" strain of measles virus isolated from a human patient with subacute sclerosing panencephalitis (SSPE). The monkeys developed antibodies to measles virus. However, no lesions were found to indicate the virus did any damage to the animal's CNS.